Breast cancer is cancer that develops from breast tissue. Breast cancer affects every 8th woman in the US. There are several types of breast cancers, classified depending on the tissue of origin. Breast cancers that begin in cells lining the milk ducts are called ductal carcinomas. If it begins in the lobules it is called lobular carcinoma. It is called invasive or infiltrating ductal or lobular carcinoma if it has spread into the surrounding tissue. When it is located only in the duct or lobule is called in situ.
The many risk factors for developing breast cancer are :
Age: The risk of developing breast cancer increases with age especially after 50.
Personal history of breast cancer: A woman with a history of cancer in one breast has a 1% to 2% chance per year of developing cancer in her opposite breast, even if other risk factors are absent.
Family history of breast cancer: Breast cancer may genetically run in the family.
Personal history of ovarian cancer: A history of ovarian cancer can increase a woman's risk of breast cancer.
Exposure to the hormones estrogen and progesterone: A woman's production of estrogen and progesterone decreases with age. But long-term exposure to these hormones increases breast cancer risk.
Race and ethnicity: It is seen that white women are more likely to develop breast cancer than black women, but among women younger than 44, the disease is more common in black women than in white women.
Lifestyle factors: Studies show that various lifestyle factors may contribute to the development of breast cancer:
- Increased weight
- Low physical activity
- Increased alcohol consumption
Signs & symptoms of breast cancer
The signs and symptoms that point to possible breast cancer are:
- Lumps or a thickening in the breast or under the arm.
- Change in size and shape of breast
- Discharge from the nipple that may or may not be bloody and may occur in only one breast
- Inwardly turned nipple or a sore in the nipple area
- Puckering, dimpling, scaliness, or new creases in the nipple or breast
- Breast becoming warm, red or swollen sometimes with a rash
- Persistent breast pain
Breast cancer diagnosis
Breast cancer may be diagnosed using imaging techniques or using the invasive surgical tests.
Imaging tests: These include diagnostic mammography, ultrasound and MRI (Magnetic Resonance Imaging).
Surgical tests: This involves biopsy of the breast tissue wherein a small sample of tissue is picked up from the breast using a needle for examination under a microscope.
The main treatment methods are four , i.e., surgery , irradiation, chemotherapy and hormone therapy.
Surgery is the removal of the cancerous tissue. There are two types of surgeries:
- Lumpectomy - It is the removal of the only the tumour tissue and a small area of cancer-free normal tissue around the tumor.
- Mastectomy - It is theremoval of the entire breast tissue by surgery.
Reconstructive (plastic) surgery
Women who have undergone a mastectomy may want to have the breast reconstructed. For this they may undergo a reconstructive plastic surgery in which breast is created using tissue taken from another part of the body or using artificial implants. When this surgery is done simultaneously with a mastectomy it is called immediate reconstruction. On the other hand it is called a delayed reconstruction if it is done some time later.Reconstructive surgery done along with a lumpectomy is called oncoplastic surgery.
External breast forms (prostheses)
An external breast prosthesis or artificial breast form is an alternative to a woman who wants to delay or not have reconstructive surgery.
In radiation therapy high energy x-rays are used to kill cancer cells. A doctor who specializes in radiation therapy is called a radiation oncologist. There are different types of radiation therapies. The most common type is called external-beam radiation therapy, which involves radiation given from a machine outside the body. When a probe in the operating room is used to give the radiation therapy, it is called intra-operative radiation. And when radiation is given by placing the source of radiation directly in the tumor, it is called brachytherapy.
Partial breast irradiation
In this technique, radiation is given directly to the tumor area, generally after a lumpectomy. This targeting of the radiation shortens the duration of radiation therapy the patient has to receive.
Intensity-modulated radiation therapy
This is a slightly more advanced technique in which the intensity of radiation is varied to target the tumor better. The use of IMRT also decreases the dose of radiation required and the risk of damage to nearby organs.
Chemotherapy is the use of specific drugs to destroy cancerous cells. Chemotherapy is done by a medical oncologist, a doctor who specializes in treating cancer with medication.
In systemic chemotherapy, the drugs are delivered through the bloodstream to reach cancer cells throughout the body. There are different ways to give the chemotherapy, including intravenous (IV) and oral.
Neoadjuvant chemotherapy is chemotherapy given prior to a surgery so as to shrink the size of the tumour. Adjuvant chemotherapy is chemotherapy given after the surgery to reduce the probability of recurrence.
In chemotherapy, a regimen (schedule) is followed to give drugs at repeating intervals for a set period of time. Common drugs for breast cancer include:
- Capecitabine (Xeloda)
- Carboplatin (Paraplatin)
- Cisplatin (Platinol)
- Cyclophosphamide (Neosar)
- Docetaxel (Docefrez, Taxotere)
- Doxorubicin (Adriamycin)
- Pegylated liposomal doxorubicin (Doxil)
- Epirubicin (Ellence)
- Fluorouracil (5-FU, Adrucil)
- Gemcitabine (Gemzar)
- Methotrexate (multiple brand names)
- Paclitaxel (Taxol)
- Protein-bound paclitaxel (Abraxane)
- Vinorelbine (Navelbine)
- Eribulin (Halaven)
- Ixabepilone (Ixempra)
Hormonal or endocrine therapy, are effective in treating cancers arising due to excessive estrogen and progestron exposure. In this treatment the hormones are blocked using specific drugs.